We discuss an intersecting \(D6\) -branes model in \(T^{6}/(Z^{2}\times Z^{^{\prime }2})\)  orentifold of type IIA theories.
All the moduli are stabilized if non-perturbative \(E2\) -brane instanton
effects are taken into account [1]}, [2]}, [3]},
and standard model spectrum can be obtained by properly arranging the intersecting branes.
Shown in table 1 are the wrapping numbers of four-stack branes \(a,b,c,d\) .
The model carries gauge groups \(U(3)_{a}\times U(2)_{b}\times U(1)_{c}\times U(1)_{d}\) , of which all the
\(U(1)_{i}\)  become massive by the Green-Schwarz mechanism except \(U(1)_{Y}\) ,
\({}Q_{Y}=\frac{1}{6}Q_{a}-\frac{1}{2}Q_{c}-\frac{1}{2}Q_{d}\) 
